Since only one medium-size torso can be made ready by March 29, Koch will wear it, the United States space agency said in a statement. However, after completing the walk, she noted how hard it was to maneuver in the large suit and requested a medium suit for this week's spacewalk.
The International Space Station (ISS) is a $100 billion (£80 billion) science and engineering laboratory that orbits 250 miles (400 km) above Earth.
But now, NASA has decided that astronaut Nick Hague will take Ms McClain's place. "There were a lot of circumstances that got us here", said Kenny Todd, manager for ISS operations and integration at NASA, during the same briefing. Christina Koch will now perform tasks in space Friday with fellow American Nick Hague - instead of Anne McClain as originally planned.
McClain became the thirteenth woman to perform a spacewalk on March 22.
These spacewalks are months late, and with cargo deliveries coming up, NASA wants to keep everything on track. McClain and Hague spent about six hours last week upgrading the station's old nickel-hydrogen batteries with more powerful lithium-ion batteries. Only one such piece will be ready by Friday, and Koch will wear it, the agency said.
Aboard the International Space Station, there are two large torsos and one extra-large torso suit ready, Quartz reported.
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As women continue to make up a greater percentage of the astronaut corps, more gender records will be set and not just in spacewalking, Dean noted.
No difference exists in a male's or female's suit, but female astronaut usually require a smaller size. And, while the comfort and safety of the astronauts remains the most important aspect of any space mission, this last-minute reassignment seems to highlight the reality that many women will have to overcome additional career roadblocks working in a world created to accommodate men. Her spacewalk came just months after cosmonaut Svetlana Savitskaya became the world's first female spacewalker on July 25 of the same year. She was selected as an astronaut for NASA in 2013.
Christina Koch will be walking on space as scheduled on March 29, but not with another female astronaut.
In NASA's history, more than 500 people have ventured out into space but only 11 percent have been women. There are two astronauts, but only one spacesuit. Astronauts go through several fittings when preparing for spacewalks to allow for this.
McClain is scheduled to make her next spacewalk on April 8.